1. Field of the Invention
The present invention relates generally to two-cycle engines and, more specifically, to a dual piston compression chamber for two-cycle engines having a primary piston and an exhaust/intake piston, said exhaust/intake piston having a plurality of one-way valve controlled passages extending therethrough to provide controlled communication between the intake ports and the compression area located between the two pistons. The present invention may also be adapted for application with spark ignition engines.
2. Description of the Prior Art
There are other two cycle engines. Typical of these is U.S. Pat. No. 780,812 issued to Radovanovic on Jan. 24, 1905.
Another patent was issued to Germaine on Dec. 24, 1907 as U.S. Pat. No. 874,634. Yet another U.S. Pat. No. 898,768 was issued to Murphy on Sept. 15, 1908 and still yet another was issued on Feb. 16 1909 to Steely as U.S. Pat. No. 912,751.
Another patent was issued to Kulage on Aug. 3, 1909 as U.S. Pat. No. 929,769. Yet another U.S. Pat. No. 931,319 was issued to Krotz on Aug. 17, 1909 and still yet another was issued on May 23, 1916 to Palmer as U.S. Pat. No. 1,183,904. A patent was issued to Carroll on Aug. 9, 1955 as U.S. Pat. No. 2,714,875 and Shapiro was issued U.S. Pat. No. 4,455,974 on Jun. 26, 1984. U.S. Pat. No. 4,964,379 was issued on Oct. 23, 1990 to August and on May 6, 1997 Erickson et al. was issued U.S. Pat. No. 5,626,106. Thompson was issued U.S. Pat. No. 5,809,947 on Sep. 22, 1998.
In combination, a cylinder having midway of its length internal peripheral exhaust-ports, a piston controlling said ports, a piston extension, a mixing-chamber therein having ports adapted to place the cylinder in communication with said chamber, the latter provided with air and gas admission ports and means to supply air and gas to said ports respectively, said supply and the admission of the mixture to the cylinder controlled by the movements of the piston extension, for the purpose set forth.
In an internal combustion engine, a pair of cylinders arranged head to head and in alignment with each other, pistons in said cylinders, a piston rod extending through the head cylinder and to which both pistons are secured, a crank shaft connected to one of the pistons, upper and lower compression chambers connected to the open ends of the cylinders, inlet ports leading from the compression chambers through the walls of the cylinders, exhaust ports leading from the cylinders and arranged to be uncovered by the pistons at the outer limits of their strokes, all the said ports being controlled by the pistons, a valve chamber intermediate the compression chambers and having a fluid inlet, and valves arranged in said valve chamber and controlling communication between the latter and the compression chambers.
In a two cycle engine, the combination of a cylinder and a piston, the space on one side of the piston being for combustion and having a clearance space so proportioned to the effective piston displacement at this end of the cylinder as to produce a compression and resulting temperature high enough to ignite the fuel to be consumed, the space on the other side of the piston being for initial compression, a valve controlled passage between the two spaces and cooperating with each other
A gas bearing supported piston assembly (2) for an internal combustion engine including a piston body (14, 14xe2x80x2) and a segmented piston ring (3) arranged to expand to compensate for wear. A piston supporting gas layer (27) is formed between the cylinder walls (8) and the exterior surface of each piston ring segment (32) by means of a plurality of restricted flow passages (40) formed in each segment (32) and extending between the inner and outer surfaces of the segment (32). In one embodiment, gas under pressure is supplied to the ring segments (32) through a single annular cavity (36) formed in piston body (14). In another embodiment, gas under pressure is supplied to the ring segments (32) through a plurality of corresponding holes (70) in piston body (14xe2x80x2).
Two pistons in adjacently situated cylinders in a twin-piston two-stroke engine share a common combustion chamber. To ensure low exhaust gas emissions with low consumption, a lean mixture is burnt whereof the complete combustion is made possible by designing the combustion chamber so that circulation of the ignited mixture takes place and the mixture burns through rapidly. The twin-piston two-stroke engine may also be devised to run with a stratified charge, the centrally arranged partition in the twin cylinder providing excellent separation between the lean and rich mixture portions.
Design Improvements are disclosed which enhance the migrating combustion chamber engine""s ability to achieve improved performance, obtain higher durability and cost less to manufacture. These include strip seals between the combustion chamber member and orbiting piston which are adapted to respond to the pressure of combustion to increase contact pressure and improve retention of the gases in the combustion chambers as well as improved porting located in at least one power block sidewall and cooperating with the migrating combustion chamber to convey hot combustion gasses from a combustion chamber to a corresponding secondary expansion chamber. The combustion chamber member may be formed of two reciprocable piston portions and a pair of separate alloy steel connecting bars coupling the piston portions together. The connecting bars made of a low thermal conductivity material to remain hot and aid in fuel evaporation. A one piece counterweight hub provides all required counterweights. It attaches to the crankshaft by a first clamp which clamps the counterweight hub onto the crankshaft, and second clamp which pulls an inside bore of the hub axially tight against an end of the crankshaft. Improvements in exhaust porting, ignition location, manifold and combustion chamber member designs as well as unique power block housing wear strips and crankshaft counterbalancing techniques are also disclosed.
A valve is provided for a piston of a two stroke engine wherein the piston has a sidewall and top and bottom surfaces with the top surface having a first opening therein and a second opening extending between the top and bottom surfaces for receiving the valve, and wherein the piston has a plurality of pressure relief openings extending between the top and bottom surfaces. The valve comprises a valve plate positioned in the opening in the top surface overlaying the pressure relief openings with the valve plate having a central opening extending parallel to the sidewall. The valve plate is movable from a seated position covering the pressure relief openings to an unseated position exposing the pressure relief openings when pressure inside the piston exceeds a predetermined value. A retainer pin has an elongated body extending through the central opening in the valve plate, a head atop the retainer pin overlying the valve plate, and a hollow end portion flared radially outward against the bottom surface of the piston to limit upward movement of the retainer pin. The valve opens on the downstroke of the piston to relieve some of the crankcase pressure allowing the piston to descend with less resistance.
While these two cycle engines may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.
A primary object of the present invention is to provide a dual piston compression chamber for two cycle engines having a primary piston and an exhaust/intake piston that cooperate with one another and form a compression chamber therebetween.
Another object of the present invention is to provide a dual piston compression chamber for two cycle engines wherein the exhaust/intake piston has a plurality of passages extending the rethrough and one-way check valves residing therein to regulate the directional flow of fuel and air from the intake ports to the compression chamber.
Yet another object of the present invention is to provide a dual piston compression chamber for two cycle engines wherein the check valves could include but are not limited to reed valves or inertial valves.
Still yet another object of the present invention is to provide a dual piston compression chamber for two cycle engines that will enable a two cycle engine to perform with a similar efficiency and emissions as a four cycle engine while maintaining a low RPM, increased torque, and greater power for engine weight.
Yet another object of the present invention is to provide a dual piston compression chamber for two cycle engines that is inexpensive to manufacture and operate.
One more object of the present invention is to provide a dual piston compression chamber for two cycle engines that is simple to use.
Additional objects of the present invention will appear as the description proceeds.
The present invention overcomes the shortcomings of the prior art by providing a dual piston compression chamber with positive displacement for two cycle engines that will produce four cycle efficiency and emissions with reduced RPM and increased torque. The present invention could be particularly useful in aircraft engines due to the greater power for a given engine weight and fewer moving parts wherein the design allows for applications with a variety of fuels.
The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawing, which forms a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawing, like reference characters designate the same or similar parts throughout the several views.
The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.